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Dive into the research topics where Anita Zenko Sever is active.

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Featured researches published by Anita Zenko Sever.


PLOS ONE | 2015

Pentadecapeptide BPC 157 Reduces Bleeding and Thrombocytopenia after Amputation in Rats Treated with Heparin, Warfarin, L-NAME and L-Arginine.

Mirjana Stupnisek; Antonio Kokot; Domagoj Drmic; Masa Hrelec Patrlj; Anita Zenko Sever; Danijela Kolenc; Bozo Radic; Jelena Šuran; Davor Bojic; Aleksandar Včev; Sven Seiwerth; Predrag Sikiric

Background BPC 157 is a stable gastric pentadecapeptide recently implicated with a role in hemostasis. While NO is largely implicated in hemostatic mechanisms, in tail-amputation-models under heparin- and warfarin-administration, both the NO-synthase (NOS)-blocker, L-NAME (prothrombotic) and the NOS-substrate L-arginine (antithrombotic), were little investigated. Objective. To investigate the effect of L-NAME and L-arginine on hemostatic parameters, and to reveal the effects of BPC 157 on the L-NAME- and L-arginine-induced hemostatic actions under different pathological condition: tail amputation without or with anticoagulants, heparin or warfarin. Methods Tail amputation, and/or i.v.-heparin (10 mg/kg), i.g.-warfarin (1.5 mg/kg/day for 3 days) were used in rats. Treatment includes BPC 157, L-NAME, L-arginine, per se and their combination. Results After (tail) amputation, with or without i.v.-heparin or i.g.-warfarin, BPC 157 (10 μg/kg, 10 ng/kg, i.p., i.v. (heparin), 10 μg/kg i.g. (warfarin)) always reduced bleeding time and/or haemorrhage and counteracted thrombocytopenia. As for L-NAME and/or L-arginine, we noted: L-arginine (100 mg/kg i.p.)–rats: more bleeding, less/no thrombocytopenia; L-NAME (5 mg/kg i.p.)-rats: less bleeding (amputation only), but present thrombocytopenia; L-NAME+L-arginine-rats also exhibited thrombocytopenia: L-NAME counteracted L-arginine-increased bleeding, L-arginine did not counteract L-NAME-thrombocytopenia. All animals receiving BPC 157 in addition (BPC 157μg+L-NAME; BPC 157μg+L-arginine, BPC 157μg+L-NAME+L-arginine), exhibited decreased haemorrhage and markedly counteracted thrombocytopenia. Conclusions L-NAME (thrombocytopenia), L-arginine (increased haemorrhage) counteraction and BPC 157 (decreased haemorrhage, counteracted thrombocytopenia) with rescue against two different anticoagulants, implicate a BPC 157 modulatory and balancing role with rescued NO-hemostatic mechanisms.


European Journal of Pharmacology | 2016

Stable gastric pentadecapeptide BPC 157 heals rat colovesical fistula

Tihomir Grgic; Dora Grgic; Domagoj Drmic; Anita Zenko Sever; Igor Petrovic; Mario Sucic; Antonio Kokot; Robert Klicek; Marko Sever; Sven Seiwerth; Predrag Sikiric

To establish the effects of BPC 157 on the healing of rat colovesical fistulas, Wistar Albino male rats were randomly assigned to different groups. BPC 157, a stable gastric pentadecapeptide, has been used in clinical applications-specifically, in ulcerative colitis-and was successful in treating both external and internal fistulas. BPC 157 was provided daily, perorally, in drinking water (10µg/kg, 12ml/rat/day) until sacrifice or, alternatively, 10µg/kg or 10ng/kg intraperitoneally, with the first application at 30min after surgery and the last at 24h before sacrifice. Controls simultaneously received an equivolume of saline (5.0ml/kg ip) or water only (12ml/rat/day). Assessment (i.e., colon and vesical defects, fistula leaking, fecaluria and defecation through the fistula, adhesions and intestinal obstruction as healing processes) took place on days 7, 14 and 28. Control colovesical fistulas regularly exhibited poor healing, with both of the defects persisting; continuous fistula leakage; fecaluria and defecation through the fistula; advanced adhesion formation; and intestinal obstruction. By contrast, BPC 157 given perorally or intraperitoneally and in µg- and ng-regimens rapidly improved the whole presentation, with both colon and vesical defects simultaneously ameliorated and eventually healed. The maximal instilled volume was continuously raised until it reached the values of healthy rats, there were no signs of fecaluria and no defecation through the fistula, there was counteraction of advanced adhesion formation or there was an intestinal obstruction. In conclusion, BPC 157 effects appear to be suited to inducing full healing of colocutaneous fistulas in rats.


PLOS ONE | 2016

Effects of Diclofenac, L-NAME, L-Arginine, and Pentadecapeptide BPC 157 on Gastrointestinal, Liver, and Brain Lesions, Failed Anastomosis, and Intestinal Adaptation Deterioration in 24 Hour-Short-Bowel Rats

Nermin Lojo; Žarko Rašić; Anita Zenko Sever; Danijela Kolenc; Darko Vukušić; Domagoj Drmic; Ivan Zoricic; Marko Sever; Sven Seiwerth; Predrag Sikiric

Stable gastric pentadecapeptide BPC 157 was previously used to ameliorate wound healing following major surgery and counteract diclofenac toxicity. To resolve the increasing early risks following major massive small bowel resectioning surgery, diclofenac combined with nitric oxide (NO) system blockade was used, suggesting therapy with BPC 157 and the nitric oxide synthase (NOS substrate) L-arginine, is efficacious. Immediately after anastomosis creation, short-bowel rats were untreated or administered intraperitoneal diclofenac (12 mg/kg), BPC 157 (10 μg/kg or 10 ng/kg), L-NG-nitroarginine methyl ester (L-NAME, 5 mg/kg), L-arginine (100 mg/kg) alone or combined, and assessed 24 h later. Short-bowel rats exhibited poor anastomosis healing, failed intestine adaptation, and gastrointestinal, liver, and brain lesions, which worsened with diclofenac. This was gradually ameliorated by immediate therapy with BPC 157 and L-arginine. Contrastingly, NOS-blocker L-NAME induced further aggravation and lesions gradually worsened. Specifically, rats with surgery alone exhibited mild stomach/duodenum lesions, considerable liver lesions, and severe cerebral/hippocampal lesions while those also administered diclofenac showed widespread severe lesions in the gastrointestinal tract, liver, cerebellar nuclear/Purkinje cells, and cerebrum/hippocampus. Rats subjected to surgery, diclofenac, and L-NAME exhibited the mentioned lesions, worsening anastomosis, and macro/microscopical necrosis. Thus, rats subjected to surgery alone showed evidence of deterioration. Furtheremore, rats subjected to surgery and administered diclofenac showed worse symptoms, than the rats subjected to surgery alone did. Rats subjected to surgery combined with diclofenac and L-NAME showed the worst deterioration. Rats subjected to surgery exhibited habitual adaptation of the remaining small intestine, which was markedly reversed in rats subjected to surgery and diclofenac, and those with surgery, diclofenac, and L-NAME. BPC 157 completely ameliorated symptoms in massive intestinal resection-, massive intestinal resection plus diclofenac-, and massive intestinal resection plus diclofenac plus L-NAME-treated short bowel rats that presented with cyclooxygenase (COX)-NO-system inhibition. L-arginine ameliorated only L-NAME-induced aggravation of symptoms in rats subjected to massive intestinal resection and administered diclofenac plus L-NAME.


Life Sciences | 2016

Stable gastric pentadecapeptide BPC 157 heals rectovaginal fistula in rats

Marko Baric; Anita Zenko Sever; Lovorka Batelja Vuletic; Zarko Rasic; Marko Sever; Domagoj Drmic; Tatjana Pavelic-Turudic; Mario Sucic; Hrvoje Vrcic; Sven Seiwerth; Predrag Sikiric

AIM Rectovaginal fistula is a devastating condition providing more than 99% of patients for surgical treatment. We hypothesized that rectovaginal fistula may be healed by therapy with stable gastric pentadecapeptide BPC 157, in consistence with its initial clinical application and effect on external fistulas. MAIN METHODS BPC 157 (10μg/kg or 10ng/kg) was given perorally, in drinking water (0.16μg/ml or 0.16ng/ml, 12ml/rat/day) till sacrifice, or alternatively, intraperitoneally, first application at 30min after surgery, last at 24h before sacrifice. Controls simultaneously received an equivolume of saline (5.0ml/kg ip) or water only (12ml/rat/day). The assessment (i.e., rectal and vaginal defect, fistula leakage, defecation through the fistula, adhesions and intestinal obstruction as healing processes) was at day 1, 3, 5, 7, 10, 14 and 21. KEY FINDINGS Regularly, rectovaginal fistulas exhibited poor healing, with both of the defects persisting, continuous fistula leakage, defecation through the fistula, advanced adhesion formation and intestinal obstruction. By contrast, BPC 157 given perorally or intraperitoneally, in μg- and ng-regimens rapidly improved the whole presentation, with both rectal and vaginal defects simultaneously ameliorated and eventually healed. The maximal instilled volume was continuously raised till the values of healthy rats were achieved, there were no signs of defecation through the fistula. A counteraction of advanced adhesion formation and intestinal obstruction was achieved. Microscopic improvement was along with macroscopic findings. SIGNIFICANCE BPC 157 effects appear to be suited to induce a full healing of rectovaginal fistulas in rats.


World Journal of Gastroenterology | 2017

Celecoxib-induced gastrointestinal, liver and brain lesions in rats, counteraction by BPC 157 or L-arginine, aggravation by L-NAME

Domagoj Drmic; Danijela Kolenc; Spomenko Ilic; Lara Bauk; Marko Sever; Anita Zenko Sever; Kresimir Luetic; Jelena Šuran; Sven Seiwerth; Predrag Sikiric

AIM To counteract/reveal celecoxib-induced toxicity and NO system involvement. METHODS Celecoxib (1 g/kg b.w. ip) was combined with therapy with stable gastric pentadecapeptide BPC 157 (known to inhibit these lesions, 10 μg/kg, 10 ng/kg, or 1 ng/kg ip) and L-arginine (100 mg/kg ip), as well as NOS blockade [N(G)-nitro-L-arginine methyl ester (L-NAME)] (5 mg/kg ip) given alone and/or combined immediately after celecoxib. Gastrointestinal, liver, and brain lesions and liver enzyme serum values in rats were assessed at 24 h and 48 h thereafter. RESULTS This high-dose celecoxib administration, as a result of NO system dysfunction, led to gastric, liver, and brain lesions and increased liver enzyme serum values. The L-NAME-induced aggravation of the lesions was notable for gastric lesions, while in liver and brain lesions the beneficial effect of L-arginine was blunted. L-arginine counteracted gastric, liver and brain lesions. These findings support the NO system mechanism(s), both NO system agonization (L-arginine) and NO system antagonization (L-NAME), that on the whole are behind all of these COX phenomena. An even more complete antagonization was identified with BPC 157 (at both 24 h and 48 h). A beneficial effect was evident on all the increasingly negative effects of celecoxib and L-NAME application and in all the BPC 157 groups (L-arginine + BPC 157; L-NAME + BPC 157; L-NAME + L-arginine + BPC 157). Thus, these findings demonstrated that BPC 157 may equally counteract both COX-2 inhibition (counteracting the noxious effects of celecoxib on all lesions) and additional NOS blockade (equally counteracting the noxious effects of celecoxib + L-NAME). CONCLUSION BPC 157 and L-arginine alleviate gastrointestinal, liver and brain lesions, redressing NSAIDs’ post-surgery application and NO system involvement.


World Journal of Gastroenterology | 2016

Esophagogastric anastomosis in rats: Improved healing by BPC 157 and L-arginine, aggravated by L-NAME

Zeljko Djakovic; Ivka Djaković; Vedran Cesarec; Goran Madzarac; Tomislav Becejac; Goran Zukanovic; Domagoj Drmic; Lovorka Batelja; Anita Zenko Sever; Danijela Kolenc; Alen Pajtak; Nikica Knez; Mladen Japjec; Kresimir Luetic; Dinko Stančić-Rokotov; Sven Seiwerth; Predrag Sikiric

AIM To cure typically life-threatening esophagogastric anastomosis in rats, lacking anastomosis healing and sphincter function rescue, in particular. METHODS Because we assume esophagogastric fistulas represent a particular NO-system disability, we attempt to identify the benefits of anti-ulcer stable gastric pentadecapeptide BPC 157, which was in trials for ulcerative colitis and currently for multiple sclerosis, in rats with esophagocutaneous fistulas. Previously, BPC 157 therapies have promoted the healing of intestinal anastomosis and fistulas, and esophagitis and gastric lesions, along with rescued sphincter function. Additionally, BPC 157 particularly interacts with the NO-system. In the 4 d after esophagogastric anastomosis creation, rats received medication (/kg intraperitoneally once daily: BPC 157 (10 μg, 10 ng), L-NAME (5 mg), or L-arginine (100 mg) alone and/or combined or BPC 157 (10 μg, 10 ng) in drinking water). For rats underwent esophagogastric anastomosis, daily assessment included progressive stomach damage (sum of the longest diameters, mm), esophagitis (scored 0-5), weak anastomosis (mL H2O before leak), low pressure in esophagus at anastomosis and in the pyloric sphincter (cm H2O), progressive weight loss (g) and mortality. Immediate effect assessed blood vessels disappearance (scored 0-5) at the stomach surface immediately after anastomosis creation. RESULTS BPC 157 (all regimens) fully counteracted the perilous disease course from the very beginning (i.e., with the BPC 157 bath, blood vessels remained present at the gastric surface after anastomosis creation) and eliminated mortality. Additionally, BPC 157 treatment in combination with L-NAME nullified any effect of L-NAME that otherwise intensified the regular course. Consistently, with worsening (with L-NAME administration) and amelioration (with L-arginine), either L-arginine amelioration prevails (attenuated esophageal and gastric lesions) or they counteract each other (L-NAME + L-arginine); with the addition of BPC 157 (L-NAME + L-arginine + BPC 157), there was a marked beneficial effect. BPC 157 treatment for esophagogastric anastomosis, along with NOS-blocker L-NAME and/or NOS substrate L-arginine, demonstrated an innate NO-system disability (as observed with L-arginine effectiveness). BPC 157 distinctively affected corresponding events: worsening (obtained with L-NAME administration that was counteracted); or amelioration (L-arginine + BPC 157-rats correspond to BPC 157-rats). CONCLUSION Innate NO-system disability for esophagogastric anastomoses, including L-NAME-worsening, suggests that these effects could be corrected by L-arginine and almost completely eliminated by BPC 157 therapy.


Vascular Pharmacology | 2018

Rat inferior caval vein (ICV) ligature and particular new insights with the stable gastric pentadecapeptide BPC 157

Jaksa Vukojevic; Marko Siroglavić; Katarina Kasnik; Tamara Kralj; Duje Stancic; Antonio Kokot; Darko Kolarić; Domagoj Drmic; Anita Zenko Sever; Ivan Barisic; Jelena Šuran; Davor Bojic; Masa Hrelec Patrlj; Ivica Sjekavica; Katarina Horvat Pavlov; Tinka Vidovic; Josipa Vlainić; Mirjana Stupnisek; Sven Seiwerth; Predrag Sikiric

Rat inferior caval vein (ICV) ligation (up to the right ovarian vein (ROV)) commonly represents a recapitulation of Virchow: with ligation leading to vessel injury, stasis, thrombosis and hemodynamic changes. We revealed that BPC 157s therapy collectively attenuated or counteracted all these events and the full syndrome. METHODS We applied BPC 157 (10 μg, 10 ng/kg) as an early regimen or as a delayed therapy. Assessment includes gross assessment by microcamera; microscopy, venography, bleeding, blood pressure, ECG, thermography, MDA and NO-level in plasma and ICV, and gene expression. RESULTS Direct vein injury, thrombosis, thrombocytopenia, prolonged bleeding were all counteracted. Also, rapid presentation of collaterals and redistribution of otherwise trapped blood volume (bypassing through the left ovarian vein (LOV) and other veins), with venous hypertension, arterial hypotension and tachycardia counteraction were shown. BPC 157-rats presented raised plasma NO-values, but normal MDA-values; in ICV tissue reverted low NO-values and counteracted increased MDA-levels. Altered expression of EGR, NOS, SRF, VEGFR and KRAS in ICV, ROV and LOV revealed increased or decreased levels, while some genes continuously remained unchanged. CONCLUSION As a new insight, BPC 157 application largely attenuated or even completely eliminated all consequences of ICV ligation in rats.


Gastroenterology | 2015

Tu2028 Pentadecapeptide BPC 157 After 70% Liver Resection in Rats

Dalibor Crvenkovic; Marko Sever; Anita Zenko Sever; Domagoj Drmic; Igor Petrovic; Zeljko Romic; Sven Seiwerth; Predrag Sikiric

We suggest that stable gastric pentadecapeptide BPC 157 improves function and liver regeneration after 70% liver resection in rats since it can rescue otherwise severe liver lesions after overdose ...


Gastroenterology | 2012

Mo2065 The Effect of Pentadecapeptide BPC 157 on Duodenocolic Fistula Healing

Darko Vukušić; Ivan Zoricic; Zarko Rasic; Marko Baric; Marko Sever; Dalibor Crvenkovic; Nermin Lojo; Domagoj Drmic; Luka Brcic; Anita Zenko Sever; Tomislav Becejac; Danijela Olujic; Andro Gliha; Robert Klicek; Sven Seiwerth; Predrag Sikiric

Background: Keratins (K) are intermediate filaments important for cell protection from stress and for protein targeting in intracellular pathways. Keratins in epithelia forming the intestinal wall consist of type II (K7, K8) and type I (K19, K18, K20) heteropolymers, where K8 and K19 are the main components. In humans, keratin mutations predispose to liver disorders, while the roles of keratins in intestinal diseases are still ambiguous. Support for keratins in intestinal health comes from the K8-null (KO) mouse manifesting early chronic colitis, similar to the human inflammatory bowel disease a major risk factor for developing colorectal cancer (CRC).We hypothesize that the K8-null related colitis would predispose mice to CRC. Further support for keratins in the CRC progression are that K8KO colonocytes hyperproliferate, are resistant to apoptosis, have abnormal differentiation patterns and interact with mitogen activated kinases. Aims: The aim was to test whether aging K8KO mice with chronic colitis have spontaneous neoplastic changes, and if the K8KO induced colonic changes render mice more susceptible to induced CRC than K8 wild type (WT). Methods and Results: 7-9 month old K8KO and WT untreated mice displayed no colon adenomas, and rare abnormal crypt foci as studied by methylene blue staining and hematoxylin and eosin staining. A low dose of the colon carcinogen azoxymethane (AOM; 10 mg/kg, 1 injection, 3 months) induced aberrant crypt foci in both strains with a trend of higher incidence in K8KO distal colon compared to WT. A high dose of AOM (15 mg/kg, 4 weekly injections) induced after 10 weeks multiple distal colon tumors (1.5-4 mm in diameter) in both genotypes, with a dramatically higher number of tumors in the K8KO distal colon (20 ± 7.5 tumors per mouse) compared to WT (4 ± 2.9 tumors per mouse). Histological analysis showed that K8KO tumors were tubular adenomas of moderate grade while the slightly smaller WT tumors where low grade dysplasias. The dysplastic changes in all tumors showed translocation of beta-catenin from the cell membrane to nuclei indicating increased Wntsignaling. Interestingly, during basal non-tumor conditions, all K8KO colonic crypt epithelial cells stained strongly for membraneous beta-catenin, while in WT preferentially brushborder epithelial cells were positive. Conclusions: K8-null mice with chronic colitis and multiple hallmarks of cancer, are not predisposed to spontaneous dysplasia or CRC but have a highly increased susceptibility to carcinogen-induced adenomas. These results show that epithelial keratin-deficiency-induced colonic changes are risk factors in colorectal tumorigenesis.


Gastroenterology | 2018

Su1486 - Bpc 157 Therapy of Portal Hypertension in Bile Duct Ligated Rats

Anita Zenko Sever; Marko Sever; Domagoj Drmic; Zeljko Romic; Sven Seiwerth; Predrag Sikiric

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